My water is crystal clear, my FC is 12.5, PH 7.6, ALK is spot on, CYA - OVER 100! I used BioGaurd Super Sol to open my pool this year and my FC levels have never dipped lower then 10.
Over the past 2 weeks I have seen large brown stains in my liner. I tried the Vitamin C test and it did nothing. I tried the puck test and it worked. Whatever it is it will not brush off without direct application on a puck. The whole pool needs to be treated to get rid of the staining. Should I just shock it with bleach?
25K gal, IG vinyl, 1/2 HP Jacuzzi pump, 200 sqft cartridge filter, Polaris 280 cleaning robot, built in 1999, new liner in 2012, Live in Crystal Lake, IL